The subject matter described and/or illustrated herein relates generally to vehicle inspection systems.
Known rail vehicle inspection systems include hot box detectors that measure the temperature of one or more components of rail vehicles. For example, some known inspection systems include infrared scanners that monitor infrared radiation emanating from wheels of the rail vehicles to determine if the wheels exhibit abnormally elevated temperatures. The infrared scanners scan across the wheels as the rail vehicle moves past the infrared scanners. If the infrared scanners detect an elevated temperature of the wheels, the inspection system may activate an alarm to notify operators of the inspection system and/or the rail vehicle. The elevated wheel temperatures may be caused by a brake that is stuck in an engaged position against a wheel. For example, in general, most of the wheels of a rail vehicle rotate along a track as the rail vehicle moves along the track. But, if a brake is stuck in an engaged position against a wheel, the wheel may not rotate or may rotate at a slower speed than the other wheels of the rail vehicle. These types of wheels may be referred to as “stuck wheels.” Friction between the stuck wheels and the rail may heat up the stuck wheels. The wheels may fail if the wheels heat up too much.
Some known infrared scanners generate signals that are representative of the temperatures sensed by the scanners. These signals may be inaccurate representations of the sensed temperatures of a wheel or other component of a rail vehicle. For example, conditions such as electrical noise in the inspection system, microphonic noise caused by flat portions of wheels and/or the rail vehicle moving relative to the scanners, sunshots impacting the radiation sensed by the scanners, misalignment of the scanners relative to the wheels, and the like, may cause the signals to inaccurately represent temperatures of a wheel. In some situations, the signals may indicate that a hot box is detected when the wheel does not actually have an elevated temperature. Such inaccurate signals may result in false alarms of hot boxes.
Thus, a need exists for a system and method of inspecting the temperatures of wheels in a rail vehicle that filters out signals that may not be representative of the temperatures of the wheels.